Hand brake



April 26, 1932. J. F. O'CONNOR HAND BRAKE Filed Jan. 6, 1950 Patented Apr. 26, 1932 UNITED STATES PATENT OFFICE JOHN OCONNOR, OF CHICAGO, ILLINOIS, ASSIGNOB- TO WT MINER, INCL, OF

CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE HAND BRAKE Application filed January 6, 1930. Serial No. 418,795.

' for railway cars that the brakes be maintained in tightened condition after being-applied and. that the same do not release during the tightening operation. In order to accomplish this result, it is the most common practice to employ in connection with hand brakes of that type in which the brake chain is wound on a drum, ratchet means to prevent retrograde rotation of the drum. An objection to this type of brake mechanism is that the addition of the ratchet means complicates the operation of the brake in that the ratchet pawl must be manipulated by the brak man. In some forms of brakes now used on railway cars, this is avoided by providing a helical gear drive between the manually operated member of the brakes and the brake drum, including a driving pinion and a cooperatinggear having their axes of rotation disposed at right angles to each other, the cooperating teeth thereof being so disposed as to offer suflicient frictional resistance in an unwinding direction to lock the gears against relative movement, thereby preventing retrograde rotation of the drum. so But this type of brake is not well adapted for mounting on the end wall of a car because it necessitates the employment of a relatively long vertical shaft at the end of the car, which shaft is subject to distortion and bending with consequent bindingon its bearings,

thus interfering with the eflicient' and successful operation of the brakes.

The main object of the invention is to provide a hand brake mechanism. particularly adapted tobe mounted on the end wall of the car, which overcomes the defects hereinbefore pointed out, by providing a drum on which the chain is wound, which is rotatable about a horizontal axis, and a hand wheel also rotatable about a horizontal axis geared to the drum, wherein sufficient internal resistance is provided to prevent unwinding of the drum through the pull exerted by the brake chain when the same is fully tightened and is being applied.

Another object of the invention is to provide a hand brake for railway cars,including a winding drum and rotary actuating means geared to the drum, wherein ratchet means is provided for preventing unwinding of the drum through the pull of the brake chain while being tightened and when fullytightened, permitting retrograde rotation of the drum by counter ratcheting action through the additional force applied when the actu ating member is manually rotated in a direction to ease 03 or back up the brakes.

A further object of the invention is to providein a hand brake mechanism of the character described in the preceding paragraph free running of the brake chain winding drum to ei'fect release of the brakes by disengaging the gearing between the, actuating means andthe drum;

Gther objects of the invention will more clearly: appear from the description and claims hereinafter following,

In the drawings, forming a part of this specification, Figure I is a front elevational view of my improved brake mechanism illus-I 7 t'rated as applied to the end wall of a car, parts of the mechanism within the housing of the brakes being illustrated in dotted lines and the hand wheel also being indicated in dotted lines. Figure'2 is a vertical, sectional view corresponding substantially to the line 22' of Figure I. Figure 3 is a vertical, sectional view in a plane at right angles to the Sectional view of Figure 2 andcorresponding substantially to the line 83 of said figure. AndpFigure 4 is an enlarged, detailed,xelevational view of the ratchet mechanism of my improved hand brake illustrating particuthe formation of the cooperating ratchet teeth thereof. 1 In carrying out my invention, I enclose the operating parts of the hand brake in a casing or housing which is preferably of two part construction, as clearly shown in Figure 2, and is mounted on the vertical end wall of the" railway car which is designated by? 10. The two part housing: comprises a back plate 11 and a cover member 12.. The back plate is of substantially circular outline and is provided with three spaced lugs 13-I3 --13:and' 1G9 a central bearing opening 14 reinforced by an annular flange in the form of a projecting boss. The cover member 12 is in the form of a substantially cylindrical box-like member having a vertical front wall 15 and a substantially annular side wall 16 formed integral therewith. The wall 16 is provided with an opening 17 at the bottom thereof through which the brake chain 18 extends. The brake chain is connected to the brake mechanism proper of'the car, not shown. The front wall 15 of the cover member 12 is provided with a bearing portion 19 located at the center thereof, which has a bearing opening in alinement with the opening 14 of the plate 11 but of larger diameter. The bearing member 19 is in the form of a boss on an inwardly offset section 20 of said front wall. Above the bearing member 19, the front wall is provided with a bearing 21 in the form of an outwardly projecting boss. The annular side .wall 16 of the cover member 12 is provided with three securing lugs at the back thereof which register with the lugs of the 1 plate 11, these lugs also being indicated by 13. The cover member 12 is secured to the back plate 11 by means'of rivets extendlng through the lugs 131.3 of the cover member and back plate and also extending through the vertical end wall of the car 10 to fix the housing to said wall. 7 7

My improved brake mechanism proper comprises broadly a chain winding drum A,

an eccentric journal member B, an operating shaft C having a pinion D thereon geared to the drum A, a hand wheel E on the outer end of the shaft C, aratchet wheel F, a ratchet member G, a spring H and an operating lever J for actuating the eccentric ournal B.

The brake drum A is rotatably journaled on the member B, the latter having front and rear trunnion members 22 and 23 and an offset or eccentric central bearing portion 24 which serves to rotatably support the chain winding drum. The journal member 23 is rotatably mounted in the bearing opening 14 of the back plate 11 and the ourna-l 22 extends through the bearing member 19 of the cover of the housing. As clearly shown in Figure 2, the journal member 22 projects outwardly of the cover plate and has the operating handle lever J fixed thereto.

The chain winding drum A has a hub portion 25 mounted on the eccentric bearing portion 24 of the member B, the 'hub being of such a width as to fit between the projecting bosses on the front and rear walls of the housing, thereby maintainingthe chain winding drum in centered position between the front and rear walls of the housing. The chain winding drum is provided with a channel or groove 26 adapted to accommodate the brake chain 18 when wound'on the drum, the channel being defined by spaced parallel walls 27 and 28.

As most clearly shown in Figure 2, the annular wall 27 is provided with laterally projecting spaced annular flanges 29 and 30, these two flanges being concentric and the flange 30 being located at the outer edge of the wall 27. The flange 30is provided with an annular series of internal gear teeth 31, thus forming an internal gear member which is integral with the chain winding drum. The flange 29 is provided with an annular series of ratchet teeth. 32 which are of special formation and will be described hereinafter more in detail. The. chain 18 is anchored to the winding drum by a lug 33 located within the channel 26 of the drum, the lug receiving the end link of the chain.

The operating shaft C is ournaled in the bearing member 21 and preferably has the pinion D, which is at the inner end of the same, formed integral therewith. The pinis in the form. of an elongated bar orblock,

as clearly shown in Figure 3, and has a curved bottom face which bears directly on the spring H, which supports the same and yieldingly urges the teeth thereof toward the ratchet member F. The spring H is in the form of an elongated strap having the ends thereof curled so as to fit about support-ing members 33-33 on the front wall 12 of the housing. The supporting member 33 are preferably formed integral with said front wall of the housing. As will be evident, the ratchet block G is adapted to have slight rocking movement on the supporting spring H in addition to conforming to curvature of spring in its movement toward and away from the ratchet member F. The block is preferably provided with two ratchet teeth 34-34 which cooperate with the teeth 32 of the ratchet member F and are complementary to the same, interfitting therewith. Each ratchet tooth 34 has a pair of reversely inclined faces 35 and 36 on opposite sides thereof. Each tooth 32 of the ratchet member F also is provided with a pair of reversely inclined faces on opposite sides thereof, the inclination of which corresponds respectively to the inclination of the faces 35 and 36 of the teeth 34 of the ratchet member G, these faces of the teeth 32 of the ratchet member F being also designated by 35 and 36 respectively.

As illustrated most clearly in Figure 4, the face 35 of each ratchet tooth is inclined at a relatively blunt angle with respect to a plane the ratchet member F. The face 36 of each tooth isinclined at'a relatively keen angle to said plane. The inclination of the faces 36 of the ratchet teeth is such that an easy ratcheting action is obtained when the chain winding drum is operated in a direction to wind the chain thereon, while the faces of the teeth of the cooperating ratchet members are so disposed as to offer substantial resistance against counter ratcheting action so as to prevent retrograde movement of the chain winding drum during progress of application of the brakes and hold the chain tightened when the brakes have been fully applied. The angularity of the faces 35 of the ratchet teeth, however, is not sufficient to entirely prevent ratcheting action, the ratchet teeth of the two ratchet members passing over each. other when power is applied to the hand wheel to rotate the chain winding drum A in an unwinding direction and with a jerking movement of the wheel.

The operation of my improved hand brake mechanism in tightening the brakes is as follows: The hand wheel E is rotated in a clockwise direction, as viewed in Figure 1, thereby actuating the pinion D and rotating the chain winding drum A in a contra-clockwise direction, the ratchetmember F ratcheting over the ratchet teeth of the block G, the cooperating faces 36,86 of the teeth 32 and 34 of said ratchetmembers at this time being operative. Through the rotation of the drum A, the chainis wound thereon, thereby tightening the brakes. Backward or retrograde movement of the chain winding drum is prevented at this time by the cooperating engaging faces 3535 of the ratchet teeth 32 and 34 of the members F and Gr, the frictional resistance between these faces being suiiicient when engaging at slow speed to overcome the force exerted through the pull of the chain while the same is being held taut. As hereinbefore pointed out, the cooperating faces 3535 of the ratchet teeth are disposed at such an angle as to prevent retrograde movement of the chain winding drum and hold the drum against rotation in an unwinding direction when the brakes have been fully tightened.

In case it is desired to back off or ease up the brakes, the hand wheel E is yanked in a contra-clockwise direction, as viewed in Figure 1, thereby effecting rotation tooth by tooth, and easing off the brake for fine adj'nsting in locating the car accurately. Rotation in this direction ofthe drum is permitted by the cooperating engaging faces 3535 of the ratchet teeth, the inclination of these teeth offering insufficient resistance to overcome the additional force applied by the jerk of the hand wheel.

When it is desired to fully release the brakes, the hand lever J isturned' from the 7 full line position'shown in Figure 1 to the dotted line position, thereby rotating the eccentric journalmember B and moving the chain windingdrum upwardly, thereby disengaging the teeth 31 thereof from the pinion D and permitting free running of the chain winding drum. In this connection, it is pointed out that the oscillating movement of the lever J is limited positively by a pair of stop lugs 37-37 provided on the cover member ofthe housing. 3? limits the downward movement of. the lever J so as to maintain the eccentric jourmember B in s'uchfias position that the teeth of the chain winding drum are in operative engagement with the pinion D. r The top h1g3? limits the upward-swinging movement of the lever J so that the eccentric jour- The lower stoplug.

nal member B willibe tumed'onlyto such-an extent as to completely disengage the teeth of the chain winding drain from the teeth of the pinioni From the preceding description taken in connection with the=d1'awings,.it will be seen that I have provided an exceedingly simple and eflicient hand brakemechanism which is especially adapted for use on the endlwall of a railway car and whereinthe operating drum which does not require the attention of the brakeman, the brakeman merely being required to operate the hand wheel of" the brakes in order to tighten the chain or ease up the brakes. FRIthEI,.t-ll6 mechanism provides for-complete release of the brakes without gear drag by umneshing the cogs.

I have herein shown and described what I ,now consider the preferred manner of carrying out my invention, but thesame is merely illustrative and I contemplate all changes and modifications that come within the scope of the claims appended hereto.

I claim:

1. In. a. hand brake, thecombination witha rotary chain winding drum having gear means rotatable therewith; of a; drive gear meshing with said gear nieans,said; drum and driving gear being rotatable about parallel axes; and yieldable means-normally opposing rotation of the drum in unwinding direction, the resistance opposing unwinding being in excess of the force exerted by'the' pullof the brake chain when the brakes are fully tightened, said resistancebeing overcome by'power applied in a direction to release the brakes, thereby permitting rotation of thedrum in unwindingdirectiom 2. In a hand brake mechanism, the combination with a rotary winding drum; of an actuating gear for driving said drum; and yieldable meansnormally holding said gear against rotation'and exerting a yieldable resistance in excess of the pull of the brake chain when the brakes are being applied and when the same are fully. tightened, said resistance being overcome by power applied in a direction to release the brakes, thereby permitting rotation of the drum in unwinding direction.

3. In a hand brake, the combination with a rotary chain winding drum having gear means rotatable therewith; of a drive gear meshing with said gear means, said drum and -driving gear being rotatable about parallel axes; means for creating yielding resistance against rotation of thedrum in both winding and unwinding directions, the resistance to unwinding being in excess of the force exerted by the pull of'the brake chain when the brakes are fully tightened; and means for disengaging the drive gear and gear means of the drum to permit unwinding of the brake chain.

4. In a hand brake, the combinationwith a rotary chain 'winding member; of a'rotary actuating member geared to said winding member for rotating the same; and means for yieldingly resisting rotation of the winding member both in chain winding direction and unwinding direction, said means offering greater resistance against unwinding than winding, the resistance offered against unwinding being in excess of the force exerted by the'pull of the brake chain when fully tightened and while being tightened, said means including a yieldingly actuated retarding member.

5. In a hand brake, the combination with a rotary chain winding member; of a rotary actuating member geared to said winding member for rotating the same; and means for yieldingly resisting rotation of the winding member both in chain winding direction and unwinding direction, said means offering greater resistance against unwinding than winding, the resistance offered against unwinding being in excess of the force exerted by the pull of the brake chain when fully tightened and while being tightened, said means including amember rotatable with the drum and a cooperating yieldingly actuating retarding -member interengaged with said first named member.

6. In a hand brake, the combination with a chain winding drum; of a pinion for rotating said drum; and ratchet means for opposing retrograde rotation of said drum, said ratchct means including two cooperating ratchet members, one of which is rotatable, said me1nbers having interengaging teeth, each tooth of each of said members having inclined faces on opposite sides thereof, one of said faces being disposed at a relatively keen angle to a plane at right angles to a plane intersecting the apex of said tooth and the axis of rotation of said rotary member to permit relative ratcheting movement of said members when the drum is operated in a chain winding direction, and the other face of each tooth being disposed at a relatively blunt angle with respect to said first named plane, to oppose relative movement of said ratchet members to hold said drum against retrograde movement, said blunt face being disposed at such an angle that the resistance to relative movement of said members is overcome when power is applied to the actuating pinion to back off the brakes.

7. In a hand brake, the combination with a chain winding drum; of an adjustable eccentric support on which the drum is mounted for rotation; a pinion for rotating said drum; ratchet means for opposing retrograde rotation of said drum, said ratchet means including two cooperating ratchet members, one of which is rotatable, said members having interengaging teeth, each tooth of each of said members having inclined faces on opposite sides thereof, oneof said faces being disposed at a relatively keen angle to a plane at right angles to a plane intersecting the apex of said tooth and the axis of rotation of said rotary member, to permit relative ratcheting movement of said members when the drum is operated in a chain winding direction, and the other face of each tooth being disposed at a relatively blunt angle with re- 1 spect to said first named plane, to oppose relative movement of said ratchet members to iold said drum against retrograde movement, said blunt face being disposed at such an angle that the resistance to relative movement of said members is overcome when power is applied to the actuating pinion toback off the brakes; and means for turning said eccentric to disengage the pinion and drum to permit free running of the drum and release of the brakes.

8. In a hand brake, the combination with a chain winding drum having ratchet means rotatable therewith; of an actuating pinion geared to said drum; and a block engaging the ratchet means, a spring supporting said block and urging it toward the ratchet means, said block and ratchet means having cooperating teeth, each tooth having reversely inclined faces on opposite sides thereof, said faces being disposed at blunt and keen angles respectively to a plane at right angles to a plane intersecting the apex of said tooth and the axis of rotation of said ratchet means.

9. In a hand brake, the combination with 1 a chain winding drum having ratchet means rotatable therewith; of an actuating pinion geared to said drum; and a ratchet block engaging the ratchet means, a leaf spring on which said block is loosely supported, said leaf spring being supported at opposite ends outwardly of the ends of the block and urging the block toward the ratchet means, said block and ratchet means having cooperating teeth, each tooth having a reversely inclined pair of faces on opposite sides thereof, said faces being disposed at blunt and keen angles respectively to a plane at right angles to a plane intersecting the apex of said tooth and the axis of rotation of said ratchet means.

In Witness that I claim the foregoing I have hereunto subscribed my name this 3rd day of January, 1930.

JOHN F. OCONNOR. 

